There's a leak dripping off the bottom of the gear box/diff area that is clearly coming from above that is blue and slightly oily. Anyone know what this fluid is so I can find the source of the leak? I checked the power steering reservoir and it seems dry and clean.

Any help appreciated.

thanks

 

blue? like washer fluid? smell it.

 

It's oily, but light. Not water at all. Smelled and felt. Here are the possibilities:
1. brake fluid - mine is light brown and not oily at all
2. engine oil - dark brown and too viscous
3. engine/radiator water - green and too light/watery
4. power steering fluid - seems colorless, but right consistency
5. transmission fluid - ??? what color, what consistency?
6. does the diff and trans share lubricant - probably as it appears to be a single transaxle unit?

thanks,

 

Both types of OEM transaxle (gearbox & differential) fluids are amber colored. I’ve heard others describe the later model hydro engine mount fluid as blue. My early model mount’s fluid was very dark but I wouldn’t have called it blue. OEM coolant is blue when new. The control arm bushing’s fluid is amber and is a light viscosity.

Look at the weep hole between the gearbox and engine block; if that is the source then it is either a leaking rear crankshaft seal or transmission input shaft seal. When you smell the liquid, the OEM transaxle fluid has a nutty aroma whereas engine oil will have a cooked petrol odor.

A leak from a power steering hose connection on the pump or at the bottom of the reservoir is easy to see; a leak at one of the top clamps is fairly common.

 

This is odd. My wifes car has a leak just like yours.
When the car is parked in the garage it has left about 5 marks on the floor.
I can't tell where its coming from. All the fluids are full.

It's oily, but light. Not water at all. Smells like nothing. Its faint blue on the floor, but colorless on my finger.
Its on the garage floor under the car slightly to drivers side (from middle)
and always makes a a 10-12" X 2" slight curve shape.
It matches no other fliud.

I've checked everything. All fluids levels are OK.
I tried to look under the car for some splash or spray marks, but nothing. :impatient
I would have to say (its hard to guess) about 3-5oz total. Could be less.

Sorry I can't help ya, its got me puzzled.

 

Are you sure you didn't run over a patch of smurfs?

Sorry couldn't help myself

 

Like I said its my wifes car, so, thats not out of the question.

 

could be coolant leaking from the thermostat or temp sensor on the driver side of the head if you take the intake off you will be able to see it

 

I'd be willing to bet that MINICORSA has it right. It's probably coolant and I've heard of 2 recent cases like this where it was dripping from the thermostat housing.

It could be washer fluid... the MINI factory stuff smells something horrible when mixed to the proper concentration, though. I think you would have noticed it.

 

OEM Antifreeze is blue.

Rich

 

Thanks for all these wonderful hints and tips. It's almost colorless on the finger as mcnuttrich says. But in concentration it's bluish. I have been topping up my engine coolant over the 2 years of ownership with red-colored antifreeze so the color is confusing...That said, I won't rule out anything.
Unfortunately all this comes about because my car is up on stands to replace the header and exhaust system. So I can't take it to the dealer and show them what's up until it's all put back together, unfortunately. However, I'm going to pull the CAI system out as it will give me access to many of the potential sources of the leak--it's clearly coming from the gearbox/diff side of the engine where many of you have pointed out are things like thermostats, and reservoirs.
I'll post when I know more! Again, thanks.

 

Well, if the original coolant is blue... and you have been topping it off..... Maybe the blue stuff satys on the botom.

 

I kept having to refill my coolant resevoir, and finally the engine started to overheat. Turns out it was a cracked thermostat, replaced under warranty.

 

Maybe Minis don't like when people use "Dr." in their NAM screen name.

 

Anybody diagnose this leak yet? I think I have the same thing. A quick look at it this AM looks like coolant (bluish) forming a crust above what appears to be a sensor of some type on left (drivers) side of head. Is this where the Cooper 'S' coolant sensor or possibly thermostat is located perhaps?

 

My Mini has the same problem and it is a leaking thermostat housing. I traced the blueish clear fluid back to the Housing on the Driver side of the cylinder head. I priced it out at my local mini dealer and it will be 300 bucks or so. It looks like i will order the OEM housing and thermostat and give it a go myself.

 

You know, you could be right! or not...
The bluish fluid is coolant, no doubt. The dealer suspects a thermostat/gasket problem, which is scary as my car has yet to complete 20k miles, but I am about to confirm, or otherwise.
The Dr will report as to the outcome. And remember, I'm not a physician, Jim.

PS yes the little thingy on the driver's side of the head is the thermostat housing.

 

The book says that not all coolants are appropriate for the MINI. Is there a particular brand that I should get to top off my leaking coolant? I can't get to the dealer in Sacramento for about a week.

 

I had a similar light bluish puddle under the car after parked for a while. Turned out to be a leaking thermostat housing...replaced under warranty at MINI dealer last week.

 

MR ECON, to raise the coolant to the proper level in the expansion tank, add water.

 

By the way, I can confirm the liquid was coolant, and the source the thermostat gasket. It's now officially fixed. Case closed, and thanks for all the hints and help.

 

Add me to the "oily blue coolant" leak list.

 

Hey Dr
Did you replace the gasket, or did you have to do the thermostat too.
How much were the parts and where did you get them from?
I'll be doing this next week I guess

Thanks to all you guys for your help

 

Yes, the gasket is part of the thermostat, as mentioned on another thread here. You cannot get the gasket separately, and it looks like a pretty special gasket with a low chance of fabricating an alternative. I don't know exactly, as I bought other things, but it cost about $40 including tax from the dealer, maybe a little less. The M7 180deg thermostat is cheaper but doesn't come with a gasket (now I know why...)

good luck.
btw, I really don't think it's easy to change out. Messy and very awkward is how I'd describe it.

 

For those of us who are blind, where is the thermostat located? The last time i had to deal with one of those was on a 94 suburban which of course looks nothing like the one on the mini.